The objective is to provide templates of anatomical structures from the human head at intervals of 1 mm from base to vertex. The horizontal sections will be parallel with a plane passing through the glabella and external auditory meatus. These will be used in interpreting the anatomy represented in CT scans obtained in the same horizontal plane, at 5 mm intervals, from base to vertex. To bring this about an LKB 2250 PMV Cryo-microtome is being modified to accommodate the human head. This instrument will be installed in the Uniformed Services University of Health Sciences where the study will be conducted in conjunction with the Department of Anatomy. The product of this effort is primarily intended for the interpretation of CT scans. A secondary objective is to provide a definitive Atlas for use by others.